Electromagnetic switch.



STEPHEN E. GAMBLE, OF PETALUMA, CALIFORNIA.

ELECTROMAGNETIC SWITCH.

Specification of Letters Patent.

PatentedFeb. 23, 1915.

Application filed October 22, 1913. Serial No. 796,615.

' matically opening or closing electric circuits. v

The object of this invention is to provide a simple, practical controlling switch for high tension circuits which is so constructed that it may be readily connected 1n circuit with any electrically-operated apparatus, for instance the motor on a singling device, etc.

The invention comprises generally a contact-making arm or switch which is so positioned that it may open or close a h1gh voltage circuit.

Another object of the invention is to provide a low voltage transformer and a secondary series of ,circuit closing means through which the main contact arm or switch bar be operated, thus avoiding the necessity of passing a high tension current through the more delicate parts or contact of the main switch operating media nism.

The invention consists of the parts and the construction and combination of parts ashereinafter more fully described and claimed, having reference to the accompanying drawings, in whichthej figure is a diagrammatic plan view, showing the switching mechanism in circuit with an electric heater.

Referring to the drawings: A indicates in general the switchboard on which is pivotally mounted, as at 2, a main switch bar 3, to the upper end of which is secured a cross bar 4, provided with insulated tips 5 and 6 and contact members 5 andlfi' adapted to partly close a circuit through contacts 7 and 8 and magnets 9 and 10. Suitably secured to the switchboard A, in sucha position that the lower end 11 of the main switch bar may project within same, is an oil chamber 12 in which is mounted a contact clip 13,

connected with the positive side of a circuit bya wire 14.

-15 indicates a wire connected with the negative side or the circuit, and the upper I end ofthe switch bar 3 is connected through a flexible connection 16 with this side of the circuit.

B indicates a low voltage transformer, the upper terminals 17 and 18 of which are connected with the negative and positive sides of the main circuit through wires 19 and 20; one of the lower opposite terminals 21 of the transformer is connected through a wire 22 with a thermostat 23, while the other lower terminal 24 of the transformer is con nected by a wire 25 with a wire 26 connecting the negative terminals of the magnets 9 and 10. One of the terminals of the thermostat, as 27, is connected by a wire 28 and a flexible connection 29 with a contact member 5, mounted on the cross bar 4, While the opposite terminal 30 of the thermostat is connected through a wire 31 and flexible connection 32 with the opposite contact member 6" on the cross bar 4.

As a practical demonstration of the electric governor, I will,take an electric heater 33 and connect it on the positive side of the circuit. This heater may be mounted in an incubator or like device in which the thercubator reaches 102, it is assumed that the thermostat arm. 23 will move into contact with the contact member 30 and close the90 rectly below the path of travel of the cross bar 4, and will thus when moved in an upward direction by the armature 10' engage with the end 60f the cross bar and move it into the dotted line position indicated at 1,

causing the main switch bar 3 to move into the dotted line position indicated at 3, thus closing a circuit through the clip 13 and point il of the switch bar. A high tension circuit is thus closed through the electric heater 33, wire14, clip 13, switch bar 3 and wire 16', which connects with the negative terminal of the high tension circuit. The

' From the followingdescription it can be.

seen that the high tension current in passing through the heater would soon cause the temperature to reach 103; the expansion of the thermostat will then immediately close the circuit at 27. A local circuit is thusestablished through the magnet 9 which immediately energizes this and causes" the armature 9, with connected pin 34L, to move in an upward direction where it will engage with the outer end-5 of the crossbar 4 and move this into the full line position shown in the drawing, causing the lower end 11 of the switch bar 3 to move out of contact with the clip 13, thus breaking the circuit through the heater and allowing the heater to remain inactive until the temperature again falls to 102, when the cycle of operation previously described will take place. The breaking of the local circuit through the points 5 and 7, by the upward movement of the pin 34, causes the flexible contact 6 to en .ge with contact 8, thus partly establishing'the other local circuit through the magnet 10.

By providing the low voltage transformer mountedand connected on the local circuits,

, at the contact clip, 13 is entirely prevented by the oil contained in the chamber 12. The device constructed and mounted as here shown may be used for automatically opening or closing circuits on motors for singling devices, pumps for water (from floats),

pumps for air (from gages), heaters ton electric brooders and incubators, etc.

While I have here shown an electric heater 33 mounted on the main circuit, it is obvious that an electrically-operated motor, or any as here shown, it becomes possible to op-,

other electrically-operated apparatus, may be installed on the circuit, similarly. 'I wish it understood that I do not Want to limit myself to the specific form of 'thermostat indicated at23, as it is obvious that many other types of thermostat may be used for the purpose of closing'the local circuits through the contacts 27 and 30.

Having thus described my invention what I claim and desire to secure by Letters Patent, is: p

1. An electromagnetic switch for control ling high tension electrical circuits comprising in combination, a moving contact making arm and a bar in swinging position, a

said arm beneath said bar, an insulated fieXible contact making finger o each end of set of magnets located on opposite sides of ing in combination, a moving contact makt ing arm and a bar in swinging position, a set of magnets located on opposite sides of said arm beneath sald bar, an insulated flexible contact making finger on each end of said bar, respective contact points for said fingers, a contact clip for the contact making arm, and an,oil tank in which said clip is set to prevent arcing.

3. An electromagnetic switch. for controlling high tension electrical circuits comprising a moving contact making arm, a bar attached to said arm at right angles thereto, a set of magnets located on opposite sides of said arm beneath. the ends of the bar. armatures for'said magnets, reciprocating pins carried by said armatures in operative [)OS1-3 tion with the ends of said bars, insulated:

contact making fingers carried by said bar, contact points for said fingers, and" an. oil

immersed contact clip for the contact mak a ing arm.

In testimony whereof I have hereunto set my hand in the presence o'l two subscribing witnesses.

STEPHEN E. GAMBLE.

Witnesses:

' \V. H. EARLY, F. L. Bowman. 

